Week 3

Question 1

What is a neuron?

Answer 1

A neuron is a cell in the nervous system that receives, processes and transmits information to other cells.

Question 2

What are the components of a neuron and what are their purposes

Answer 2

Dendrites: Receive stimulation from sensory receptors
Soma: Cell body containing the nucleus.
Axon: Long extended fibre that neural impulses travel on.
Terminal buttons: Bulb-like neurotransmitters at the end of the axon

Question 3

What are the 3 classes of Neurons?

Answer 3

Sensory neurons: From sensory receptors to central nervous system
Motor neurons: From central nervous system to glands and muscles
Inter-neurons: From sensory neurons or inter-neurons to motor neurons

Question 4

Describe the 2 properties of the Action Potential

Answer 4

All-or-none law: Size of the action potential is not affected by increased stimulation beyond the threshold level
Refractory period: Period where further stimulation can’t cause any action potential

Question 5

What are the principles of firing a neuron?

Answer 5

When a neuron is resting it is given negative charge inside the cell membrane, and positive charge on the outside

When a neuron is stimulated, its cell membrane is depolarised or hyper-polarised. These are called “graded potentials”

If the cell reaches firing threshold, the cell will be released.

Question 6

What are the 2 receptors?

Answer 6

Excitatory

Inhibitory

Question 7

What is a synapse?

Answer 7

A synapse is a gap between one neuron and another.

Question 8

Define neurotransmitters

Answer 8

Neurotransmitters are chemical messages full of information.

Question 9

Define synaptic transmittion

Answer 9

Relying of info from one neuron to another across the synaptic gap.

Question 10

Where are neurotransmitters stored?

Answer 10

Neurotransmitters are stored in the vesicles or pre-synaptic cell

Question 11

Describe the process of a neuron being released?

Answer 11

A neuron is released in response to action potential from the pre-synaptic membrane. The molecules diffuse and bind to the post-synaptic receptors. The receptor binding produces a graded potential in the next cell

Question 12

What is the function of Acetyl-choline?

Answer 12

It activates the motor neurons that control skeletal muscles.
Regulates attention, arousal and memory
Can be stimulated by nicotine

Question 13

What is the function of dopamine?

Answer 13

In control of voluntary movement.
Decreased levels: Parkinsons
Over-activity: Schizophrenia

Question 14

What is the function of NE?

Answer 14

Modulates mood and arousal

Question 15

What is the function of serotonin?

Answer 15

Regulates sleep, wakefulness and eating

Abnormal: Depression or OCD

Question 16

What is the function of endorphins?

Answer 16

Pain relief, pleasurable emotions, addictive

Question 17

What is the Endocrine system?

Answer 17

A collection of glands that release hormones into the blood stream. It is a private system for inter-cellular communication

Question 18

What is the pituitary?

Answer 18

Hormones that influence secretions of the thyroid, pancreas, adrenals and gonads.

Question 19

Describe the parts of the pitultary?

Answer 19

Thyroids: Produces hormones that regulate metabolic rate
Adrenal glands: Controls salt and carb metabolism, secretes arousal and sleep hormones
Pancreas: Releases insulin and glucogen to control sugar metabolism
Gonads: Overies and testes produce hormones that produce secondary sexual characteristics.